My "dogbone" shorted out!

[MSHappyCampers]

Our house has a 30A receptacle outside. I have a 30a extension cord plugged into it, then a 30A-50A dogbone adapter to the 50A shorepower cable from the MH.

We were sitting the the den when we saw a HUGE amount of white smoke blowing across the patio from the direction of the MH! I was sure that the MH was on fire! I rushed outside and the dogbone connection to the 30A extension cord was blazing and throwing sparks everywhere! It was laying against the vinyl siding on the house, which was also on fire!

I quickly unplugged the 30A cord from the wall receptacle and used a water hose to extinguish the fire!

I want to install a 50A receptacle on the wall to eliminate the extension and dogbone. Since this is a 120VAC circuit, can I just wire the two "hot" legs on the wall outlet together? I'm assuming that's what the dogbone does but want to be sure. Below is the outlet I plan to order.

https://www.amazon.com/gp/product/B0...KIKX0DER&psc=1

The scary thing about this is that had we not been home we would probably lost the house and the MH! The weird thing about this is that the house circuit breaker did not trip!

[Old-Biscuit]

30A only has ONE Hot, ONE Neutral, ONE Ground
*50A has 2 HOTS

The Dogbone takes the ONE HOT and jumpers it to both Hots on the 50A
*RV is only getting 30A total

50A Receptacle requires TWO hots --each fed from Separate 50A Circuit Breaker

**Need to pull an extra wire (#6 ga) and install double 50A CB in Main AC Panel of house

Should check that 30A CB in house ---sparking/smoking dogbone should have tripped






ON EDIT:
Reading your post again.......you want to use the same 30A CB/circuit currently at receptacle and replace the 30A with a 50A receptacle jumpering the ONE 30A hot to both 50A terminals on receptacle
Correct?
YES that can be done.......not up to code

you can have a 50A Outlet fed by 2 separate 30A CBs

[Warhorse6]

Clearly not an electrician, but I would make sure your wiring gauge for the outlet is sufficient to support 50 amp. Suspect you may also need to upgrade your circuit breaker. Glad you caught the issue in time.

[Jkwilson1989]

The dogbone does indeed connect the single hot lead from the 30A 120V outlet to both hots on the 50A cord.

In theory, your plan is better than a dogbone of unknown quality.

Before you proceed, I’d want to see that you do have a 30A breaker protecting your outlet. The likely failure was a poor quality connection overheating, but best to be sure.

[MSHappyCampers]

This is what it looks like! Not sure why it's sideways!

[MSHappyCampers]

Originally Posted by Old-Biscuit

30A only has ONE Hot, ONE Neutral, ONE Ground
*50A has 2 HOTS

The Dogbone takes the ONE HOT and jumpers it to both Hots on the 50A
*RV is only getting 30A total

50A Receptacle requires TWO hots --each fed from Separate 50A Circuit Breaker

**Need to pull an extra wire (#6 ga) and install double 50A CB in Main AC Panel of house

Should check that 30A CB in house ---sparking/smoking dogbone should have tripped






ON EDIT:
Reading your post again.......you want to use the same 30A CB/circuit currently at receptacle and replace the 30A with a 50A receptacle jumpering the ONE 30A hot to both 50A terminals on receptacle
Correct?
YES that can be done.......not up to code

you can have a 50A Outlet fed by 2 separate 30A CBs

Yes, that's the plan. Wouldn't that be the same thing that the dogbone is doing? I don't have any way to run two 120VAC circuits to the outlet.

[MSHappyCampers]

Originally Posted by Jkwilson1989

The dogbone does indeed connect the single hot lead from the 30A 120V outlet to both hots on the 50A cord.

In theory, your plan is better than a dogbone of unknown quality.

Before you proceed, I’d want to see that you do have a 30A breaker protecting your outlet. The likely failure was a poor quality connection overheating, but best to be sure.

I plan to replace that 30A breaker for sure!

[bigb56]

The connection most likely overheated either at the plug blades or the dogbone had some broken strands at the blade connection from repeated use/bending or from poor construction and the load was sufficient to cause it to get hot enough over time to start a fire. The breaker didn't trip because there was no overload. This happens with engine block heaters when the cords get old, strands break inside the cord and the connection eventually becomes what is known as a "glowing connection". Over several hours a glowing connection gradually starts burning the plastics around it with a very hot fire which, if undetected, can burn the entire vehicle down. The breaker doesn't trip until enough plastic burns to expose bare conductors which then make contact and trip it, but by then the fire is well under way. Were you running heat pumps or space heaters?

[MSHappyCampers]

Originally Posted by bigb56

The connection most likely overheated either at the plug blades or the dogbone had some broken strands at the blade connection from repeated use/bending or from poor construction and the load was sufficient to cause it to get hot enough over time to start a fire. The breaker didn't trip because there was no overload. This happens with engine block heaters when the cords get old, strands break inside the cord and the connection eventually becomes what is known as a "glowing connection". Over several hours a glowing connection gradually starts burning the plastics around it with a very hot fire which, if undetected, can burn the entire vehicle down. The breaker doesn't trip until enough plastic burns to expose bare conductors which then make contact and trip it, but by then the fire is well under way. Were you running heat pumps or space heaters?

Only one space heater.

[ArtJoyce]

I have seen through the years the different dogbone's melt including one I had. Most of them just are not made well.

What happens is inside they develop a poor connection with a micro gap. The connection continues to work through micro arching which is where the heat comes from. The circuit is not overloading so no breaker is tried.

I still use dogbone's. But now I come back and fell the dogbone for heat. Any heat, even warm I trash the dogbone.

You could do what you were thinking of on your 30 outlet. Its not to code and would be very confusing. I would label the outlet with a sticker as to what it is. I have a 50 amp out that has two phase 30 amp wire and breaker. It was an old welder circuit and I never replaces the 10 guage wire with #6.

[Xmcdog]

Joe,
I would suggest strongly that you hire an electrician to put in the correct outside outlet that you need. Sorry but with electricity, if you have to ask you shouldn't do it. Stay safe and hire a pro.
Glad you were there to catch your fire.

[Winemaker2]

Originally Posted by Xmcdog

Joe,

I would suggest strongly that you hire an electrician to put in the correct outside outlet that you need. Sorry but with electricity, if you have to ask you shouldn't do it. Stay safe and hire a pro.

Glad you were there to catch your fire.

Agree
Above proves you can start a fire with less than 30A and without tripping breakers.
Lots of house fires get started from 15A circuits and lamp cords.
The benefit of dog bones is that are out in open air... make connections in a wall or elect box and if not done correctly you have moved the source closer to combustibles.

[bigb56]

Originally Posted by MSHappyCampers

Only one space heater.

That's 1,500 watts and plenty enough to expose a weak connection, For that kind of draw everything must be in good condition, all strands of wire intact and connected at terminals, terminals tight and blades clean and fitting tightly into sockets. An extension cord can exacerbate the situation.
Some, if not all dogbones and many cords are put together with solder or tinned leads at the terminations and once they are overheated enough the solder can melt and create a loose connection. A fire can easily start with current well under the circuit breaker rating.

You might also consider cutting out a square of siding and replacing with stainless steel around the outlet.

[dizcom]

Originally Posted by Tedo

Clearly not an electrician, but I would make sure your wiring gauge for the outlet is sufficient to support 50 amp. Suspect you may also need to upgrade your circuit breaker. Glad you caught the issue in time.

Yep, and that your run isn't too long to drop the voltage too far. This also takes the problem you encountered and moves it inside your home. You're better off running a whole new 50 amp run, with circuits, rather than trying to jury rig something. It's what we did. It's not as hard as it might seem.